现有的向量加权稳健波束形成方法只有在指向误差较小的情况下才能有效估计目标的信号功率；矩阵加权波束形成方法在指向误差较大时，虽然可以估计目标的信号功率，但是它的系统实现复杂度与向量加权稳健波束形

成方法相比较大。针对以上问题，该文提出基于半正定秩松弛(SDR)方法的稳健波束形成，该方法优化模型中的目标函数与Capon 算法的目标函数相同，优化变量为加权向量的协方差矩阵，并约束方向图的主瓣幅度波动范围、旁瓣电平，协方差矩阵的秩为1。-The existing vector weighted robust beamforming is able to estimate the signal power of target only in

situations of a small steering angle error. For a larger steering angle error case, although the matrix weighted

beamforming can effectively estimate the signal power of the target as well, the system implementation is more

complicated than above mentioned vector weighted. In order to solve these problems, this paper presents a new

robust beamforming approach based on SemiDefinite rank Relaxation (SDR). Detailed descr iption of the proposed

method are given as follows: the optimal model has the same objective as that of the Capon algorithm　the

optimization variable is the covariance matrix of weight vector with constraints posed on the ripple of mainlobe

amplitude and sidelobe level, and the rank of covariance matrix is 1.